The supplying of microorganism-free water to users is a continuing technological problem, although water treatment is an old technology which finds use in virtually every city. Typically, the water is chlorinated to destroy microorganisms, with the chlorinating agents being added in quantities so that only minimal amounts of chlorine remain in the water after microorganisms and other organic materials have been neutralized by the free chlorine present.
One specific technical problem that remains to the present day is the problem with water that sits in stagnant manner in faucets between uses. Such water can exhibit a growth of microorganisms. Thus, when the faucet is turned on after a long period of disuse, the first aliquot of water delivered can have a relatively high bacterial count, even if the water was initially filtered and chlorinated.
This problem is addressed in Norton U.S. Pat. Nos. 4,676,896; 4,980,056; and 5,045,198. In the first cited patent, a faucet-mounted ultraviolet irradiation unit is provided for purification of water at the faucet, to inactivate bacteria that may have grown upstream in the line during a period of inactivity, and also to inactivate bacteria and virus present in the water as supplied. Such a unit of course requires electric power.
By this invention, a faucet-mounted water purifier is provided which requires no electric power, and which can be used for the reliable removal of bacteria, and even virus, from water as it passes through the faucet. Because the invention of this application is a faucet-mounted unit, it is capable of removing microorganisms from water which has remained in stagnant manner in the faucet region for a substantial period of time, with resulting bacterial growth. The faucet-mounted purifier of this invention can remove bacteria that are downstream from the conventional filters and irradiators of the prior art which are customarily used in water lines, so that even initial aliquots of water from a freshly turned-on faucet will be substantially microorganism free.